Instantly find explanations, causes, and resolution steps for every Claim Adjustment Reason Code (CARC) and Remark Code.
Claim Adjustment Reason Codes (CARC) explain why a payment differs from what was billed. Every 835 ERA and EOB uses these standardized codes.
Search any code or keyword above. Each page includes the full description, common causes, resolution steps, and appeal guidance.
Each denial code page also links to a dedicated Remark Code page — optimized for providers searching for ERA remark code context.
Most denials are reversible. Our guides walk you through the correct steps to correct, resubmit, or formally appeal each denial type.
| Code | Description | View |
|---|---|---|
| 960 | Denied. Side of body treated disagrees with the side of body accepted as injured in t… | Details → |
| 961 | Denied. This is not a Washington state industrial injury. | Details → |
| 962 | Adjusted. Remaining balance from this procedure fund paid. Notify the vocational coun… | Details → |
| 963 | This deduction is taken for payment(s) made in error. | Details → |
| 964 | This payment is made for a deduction which was taken in error. | Details → |
| 965 | Denied. Injured worker expired prior to date of this service. | Details → |
| 966 | This is a rebill, check for prior payment. If none received, resubmit. | Details → |
| 967 | No payment made because there were no charges listed on your billing. | Details → |
| 968 | Denied. The listed value for this service includes the professional component. | Details → |
| 969 | Denied. Provider tape billing fee is limited to one charge per claim in any 30 day pe… | Details → |
| 970 | Reopening denied. | Details → |
| 971 | Processed under correct claim number for this date/nature of injury. Please note for … | Details → |
| 972 | Waiting for signature certifying the delivery of services. | Details → |
| 973 | Denied. Excess invalid/missing detail on this bill. See billing instructions. Revise … | Details → |
| 974 | Rebill dental professional fees on L&I Statement for Miscellaneous Service bill form. | Details → |
| 975 | Denied. L&I is not responsible for 'no show' appointments. | Details → |
| 976 | This fee is payment for medical records. | Details → |
| 977 | Please note the provider number. This is the number you must use when billing physici… | Details → |
| 978 | Please note the provider number. This is the number you must use when billing pharmac… | Details → |
| 979 | Please note the provider number. You must use this number when billing for pain clini… | Details → |
| 980 | Please note the claim number. It must be used when billing for this injury for this i… | Details → |
| 981 | Note provider number and name. They must be on all billing sent to L&I. | Details → |
| 982 | L&I has no provision for payment of provider administrative costs. | Details → |
| 983 | Denied. Refill of this drug in less than 30 days must be justified by the attending p… | Details → |
| 984 | Payment made to correct your account for the refund which you made to L&I in error. | Details → |
| 985 | Denied. This is a Social & Health Services bill sent to us in error. | Details → |
| 986 | NDC number invalid or missing. If equipment, resubmit on Statement for Miscellaneous … | Details → |
| 987 | Denied. Service was not substantiated by attending physician and requires prior autho… | Details → |
| 988 | The date of service is before the reopen date. | Details → |
| 989 | Denied. Claim number missing. Resubmit new bill with claim number. | Details → |
| 990 | Not paid. The provider must bill L&I and return your full payment directly to you. | Details → |
| 991 | Denied. Drug quantity is invalid. Resubmit using metric measuring only. | Details → |
| 992 | Bill paid. You must reimburse the insurance company the total amount they paid for th… | Details → |
| 993 | Travel expense has been authorized only for the injured worker. | Details → |
| 994 | Do not include line items for services which you are crediting and no payment is due. | Details → |
| 995 | L&I is not responsible for payment while injured worker is in DNR Forest Camp. | Details → |
| 996 | Payment to cancel balance of interim credit in this provider account. Credit transfer… | Details → |
| 997 | Refer to the accompanying explanation of benefits code listed for this service. | Details → |
| 998 | This transaction is a refund from this provider. | Details → |
| 998 | Negative Check This amount has been credited to a prior adjustment. | Details → |
| 999 | This adjustment is made per your request on a previously processed bill. | Details → |
| 999 | Reversed Claim This claim represents an adjustment to claim ___ processed on mm/dd/yy… | Details → |
| 1001 | MUE Edit The units of service billed exceeds our acceptable maximum units (MUE-medica… | Details → |
| 1002 | Incorrect TOB ESRD Hospitals with a Medicare certified renal dialysis facility should… | Details → |
| 1003 | EOP Required Please resubmit with a copy of the Explanation of Payment from the prima… | Details → |
| 1004 | MSP This claim has been paid in full by the primary carrier. | Details → |
| 1005 | HH Treatment Code not billed 18 digit Alpha/Numeric MCR Treatment Authorization code … | Details → |
| 1006 | Resubmit with RUGs code Resubmit claim with valid RUGS code. | Details → |
| 1007 | Multiple rev code 0023 Multiple instances of revenue code 0023 billed on a single cla… | Details → |
| 1008 | Missing or invalid Admit Date Admit date is missing or invalid. | Details → |
| 1009 | Negative charges not allowed Negative charges are not permitted on a claim service li… | Details → |
| 1011 | Team surgeon not allowed Team surgeon not allowed. | Details → |
| 1012 | HCPCS required Surgical procedure requires HCPCS. | Details → |
| 1013 | Benefit not separately reimbursed This benefit is not separately reimbursed. | Details → |
| 1014 | Member not within age range for benefit The benefit for the service rendered is not w… | Details → |
| 1015 | Only one anesthesia code per surgical session Only one primary anesthesia should be r… | Details → |
| 1017 | Service Not Covered Service Not Covered | Details → |
| 1018 | Missing EMS report Need ambulance EMS report. | Details → |
| 1019 | Invalid anesthesia code Need valid anesthesia code. | Details → |
| 1020 | Admit date under previous contract Service dates not matching proper 60 Day Episodic … | Details → |
Medical claim denial codes — formally known as Claim Adjustment Reason Codes (CARC) — are standardized identifiers maintained by the X12 standards body and used across all Medicare, Medicaid, and commercial payer 835 electronic remittance transactions. When a claim is paid at a different amount than billed, at least one CARC code must accompany the remittance advice to indicate the specific reason for the adjustment.
The most frequently encountered codes include CO-16 (missing or invalid claim information), CO-45 (charges exceeding fee schedule), PR-1 (patient deductible), CO-29 (timely filing deadline exceeded), and CO-4 (procedure code inconsistent with modifier). Each represents a distinct, actionable reason that has a defined resolution pathway.